Tools - Multi-Use Tester Usage

91mitsubishi03

NO. TSB-91-00-006

DATE April, 1991

MODEL 3000GT


SUBJECT:

3000GT MULTI-USE TESTER USAGE


PURPOSE

This bulletin describes Multi-Use-Tester (MUT) usage on 1991 3000GT vehicles.





PROPER MUT CONNECTION/DISCONNECTION

Certain precautions must be taken before connecting or disconnecting the MUT to 3000GT vehicles. An adapter harness MB991377-01 must be connected to the MUT and the ignition key MUST be in the "OFF" position before connecting the harness to the diagnostic connector. If the MUT and the adapter harness assembly is connected or disconnected to the diagnostic connector when the key is in the "ON" position, diagnostic code number 55 may be stored.





NOTE: If the MUT is disconnected from the diagnostic connector when the ignition key is "ON," technicians should check the ABS system for code 55 and erase the code as shown in the diagnostic flow chart on Page 2.


CODE 55 DIAGNOSIS

Since a code 55 (ABS Control Unit error) may result from an improper MUT connection sequence, refer to the flow chart shown on page 2 for the proper diagnostic procedures.

The flow chart describes how to properly hook up the MUT to the vehicle's diagnostic connector and the steps to take when a code 55 is displayed.


ADAPTER HARNESS USE

When connecting the MUT to the vehicle's diagnostic connector make certain that the adapter harness MB991377-01 is installed between the MUT and the connector. The adapter harness includes electronic components that stabilize the ABS data output.


FRONT WHEEL SENSOR MALFUNCTION DISPLAY

The MSN-3 ROM pack incorrectly displays the location of the front wheel sensor failures. Any time a trouble code is generated for a front wheel sensor, the MUT displays the incorrect (opposite) side of the car. For example if the trouble code indicates a left front sensor malfunction, the right front sensor is suspect. This condition will be corrected in the MSN-4 ROM pack (due for release in late 1991).


GENERAL ABS INFORMATION

When the MUT is connected to the diagnostic connector, and the ignition is turned on, the ABS Warning Light will be on. This indicates that the ABS ECU is in the "TEST MODE."

The ABS system will store and display one diagnostic code at a time. After completing any ABS repairs erase the diagnostic code and disconnect the MUT. Then the vehicle should be driven at least one mile (varying speeds and braking). This will allow any remaining diagnostic codes to be stored in the ABS ECU. If the warning light comes on during the test drive, it will be necessary to recheck the ABS system for additional diagnostic codes.


ABS Warning Lamp Operation

The ABS warning light will light up 1) When the ECU detects a malfunction in the Anti-Lock Brake system; 2) When the Multi Use Tester is connected to the vehicle's diagnostic connector; 3) During engine starting; 4) After the vehicle starts, it will blink and then go out.

IF THE ABS WARNING LIGHT IS ILLUMINATED DURING NORMAL DRIVING CONDITIONS, THE ABS SYSTEM IS NOT OPERATING PROPERLY AND SHOULD BE DIAGNOSED USING THE PROCEDURES DESCRIBED IN THIS BULLETIN AND IN THE SERVICE MANUAL!